lyx_mirror/src/support/Messages.cpp

/* \file Messages.cpp
 * This file is part of LyX, the document processor.
 * Licence details can be found in the file COPYING.
 *
 * \author Lars Gullik Bjønnes
 *
 * Full author contact details are available in file CREDITS.
 */

#include <config.h>

#include "support/Messages.h"

#include "support/debug.h"
#include "support/docstring.h"
#include "support/environment.h"
#include "support/lstrings.h"
#include "support/Package.h"
#include "support/unicode.h"

#include "support/lassert.h"

#include <cerrno>

#  define N_(str) (str)              // for marking strings to be translated

using namespace std;

namespace lyx {

void cleanTranslation(docstring & trans) 
{
	/*
	  Some english words have different translations, depending on
	  context. In these cases the original string is augmented by
	  context information (e.g. "To:[[as in 'From page x to page
	  y']]" and "To:[[as in 'From format x to format y']]". This
	  means that we need to filter out everything in double square
	  brackets at the end of the string, otherwise the user sees
	  bogus messages. If we are unable to honour the request we
	  just return what we got in.
	*/
	size_t const pos1 = trans.find(from_ascii("[["));
	if (pos1 != docstring::npos) {
		size_t const pos2 = trans.find(from_ascii("]]"), pos1);
		if (pos2 != docstring::npos) 
			trans.erase(pos1, pos2 - pos1 + 2);
	}
}

} // lyx


#ifdef ENABLE_NLS

#  ifdef HAVE_LOCALE_H
#    include <locale.h>
#  endif

#  if HAVE_GETTEXT
#    include <libintl.h>      // use the header already in the system *EK*
#  else
#    include "intl/libintl.h"
#  endif

using namespace lyx::support;

namespace lyx {

// This version use the traditional gettext.
Messages::Messages(string const & l)
	: lang_(l), warned_(false)
{
	// strip off any encoding suffix, i.e., assume 8-bit po files
	size_t i = lang_.find(".");
	lang_ = lang_.substr(0, i);
	LYXERR(Debug::LOCALE, "language(" << lang_ << ")");
}


void Messages::init()
{
	errno = 0;
	string const locale_dir = package().locale_dir().toFilesystemEncoding();
	char const * c = bindtextdomain(PACKAGE, locale_dir.c_str());
	int e = errno;
	if (e) {
		LYXERR(Debug::LOCALE, "Error code: " << errno << '\n'
			<< "Directory : " << package().locale_dir().absFileName() << '\n'
			<< "Rtn value : " << c);
	}

	if (!bind_textdomain_codeset(PACKAGE, ucs4_codeset)) {
		LYXERR(Debug::LOCALE, "Error code: " << errno << '\n'
			<< "Codeset   : " << ucs4_codeset);
	}

	textdomain(PACKAGE);
}


string Messages::language() const
{
	// get the language from the gmo file
	string const test = N_("[[Replace with the code of your language]]");
	string const trans = to_utf8(get(test));
	if (trans == test) {
		LYXERR0("Something is weird.");
		return string();
	} else
		return trans;
}


bool Messages::available(string const & c)
{
	static string locale_dir = package().locale_dir().toFilesystemEncoding();
	string code = c;
	// this loops at most twice
	while (true) {
		string const filen = locale_dir + "/" + code 
			+ "/LC_MESSAGES/" PACKAGE ".mo";
		if (FileName(filen).isReadableFile())
			return true;
		if (contains(code, '_'))
			code = token(code, '_', 0);
		else return false;
	}
	return false;

}

namespace {

// Trivial wrapper around gettext()
docstring const getText(string const & m)
{
	// FIXME: gettext sometimes "forgets" the ucs4_codeset we set
	// in init(), which leads to severe message corruption (#7371)
	// We set it again here unconditionally. A real fix must be found!
	LASSERT(bind_textdomain_codeset(PACKAGE, ucs4_codeset), /**/);

	char const * m_c = m.c_str();
	char const * trans_c = gettext(m_c);
	docstring trans;
	if (!trans_c) {
		LYXERR(Debug::LOCALE, "Undefined result from gettext for `" << m << "'.");
		trans = from_ascii(m);
	} else if (trans_c == m_c) {
		//LYXERR(Debug::LOCALE, "Same as entered returned");
		trans = from_ascii(m);
	} else {
		//LYXERR(Debug::LOCALE, "We got a translation");
		// m is actually not a char const * but ucs4 data
		trans = reinterpret_cast<char_type const *>(trans_c);
	}

	cleanTranslation(trans);

	return trans;
}

}


docstring const Messages::get(string const & m) const
{
	if (m.empty())
		return docstring();

	// Look for the translated string in the cache.
	TranslationCache::iterator it = cache_.find(m);
	if (it != cache_.end())
		return it->second;

	// The string was not found, use gettext to generate it
	docstring trans;
	if (!lang_.empty()) {
		// This GNU extension overrides any language locale
		// wrt gettext.
		LYXERR(Debug::LOCALE, "Setting LANGUAGE to " << lang_);
		EnvChanger language_chg("LANGUAGE", lang_);
		// However, setting LANGUAGE does nothing when the
		// locale is "C". Therefore we set the locale to
		// something that is believed to exist on most
		// systems. The idea is that one should be able to
		// load German documents even without having de_DE
		// installed.
		LYXERR(Debug::LOCALE, "Setting LC_ALL to en_US");
		EnvChanger lc_all_chg("LC_ALL", "en_US");
#ifdef HAVE_LC_MESSAGES
		setlocale(LC_MESSAGES, "");
#endif
		trans = getText(m);
	} else
		trans = getText(m);
		

#ifdef HAVE_LC_MESSAGES
	setlocale(LC_MESSAGES, "");
#endif

	// store translation in cache
	pair<TranslationCache::iterator, bool> result =
		cache_.insert(make_pair(m, trans));

	LASSERT(result.second, /**/);

	return result.first->second;
}

} // namespace lyx

#else // ENABLE_NLS
// This is the dummy variant.

namespace lyx {

Messages::Messages(string const & /* l */) {}

void Messages::init()
{
}


docstring const Messages::get(string const & m) const
{
	docstring trans = from_ascii(m);
	cleanTranslation(trans);
	return trans;
}

std::string Messages::language() const
    {
        return string();
    }

bool Messages::available(string const & /* c */)
{
	return false;
}

} // namespace lyx

#endif

#if 0

-#include <locale>

namespace lyx {

// This version of the Pimpl utilizes the message capability of
// libstdc++ that is distributed with GNU G++.
class Messages::Pimpl {
public:
	typedef messages<char>::catalog catalog;

	Pimpl(string const & l)
		: lang_(l),
		  loc_gl(lang_.c_str()),
		  mssg_gl(use_facet<messages<char> >(loc_gl))
	{
		//LYXERR("Messages: language(" << l << ") in dir(" << dir << ")");

		string const locale_dir = package().locale_dir().toFilesystemEncoding();
		cat_gl = mssg_gl.open(PACKAGE, loc_gl, locale_dir.c_str());

	}

	~Pimpl()
	{
		mssg_gl.close(cat_gl);
	}

	docstring const get(string const & msg) const
	{
		return mssg_gl.get(cat_gl, 0, 0, msg);
	}
private:
	///
	string lang_;
	///
	locale loc_gl;
	///
	messages<char> const & mssg_gl;
	///
	catalog cat_gl;
};

} // namespace lyx

#endif